柱形偏置短叶片低比转数离心泵数值模拟研究

Numerical Simulation of Centrifugal Pump at Low Specific Speed with Deviated Short Cylindrical Blades

选取比转数为66的IS50-32-125型离心泵为研究对象,并对其加装了柱形偏置短叶片。采用数值模拟的方法对两种泵的内部流场和外性能进行研究,发现:加装柱形偏置短叶片的离心泵能够有效改善离心泵内的流动状况,减小叶轮内部的压力波动,从而减小流动损失;柱形短叶片的存在增大了排挤系数,对长叶片背面的液流起到补功作用,能够有效控制长叶片背面流体的分离和脱流,并在叶轮出口部位具有较为理想的流动状态;加装柱形短叶片的离心泵扬程和水力效率,在设计工况下分别提高了13%和3%。

Making use of the numerical simulation, the IS50-32-125 centrifugal pump with specific speed of 66 was taken as the object of study, and then this pump was equipped with deviated short cylindrical blades. Investigating into two pumps＇ inner flow fields and external characteristics shows that, the pump with deviated short cylindrical blades can effectively reduce pressure pulsation at impeller＇ s exit to make pressure distribu- tion in the pump more uniform, the shock loss reduced and the outlet pressure improved; the deviated short cylindrical blades＇ existence can enlarge the excretion coefficient and make up the flow and control the flow separation at the back of long blades as well as create an idea flow at the impeller＇ s outlet. The head and wa- terpower efficiency of the pump with short cylindrical blades can be increased by 13% and 3% under working conditions.